Qur'an · Ar-Ra'd 13:28
سُورَةُ الرَّعۡدِ
ٱلَّذِينَ ءَامَنُوا۟ وَتَطْمَئِنُّ قُلُوبُهُم بِذِكْرِ ٱللَّهِ ۗ أَلَا بِذِكْرِ ٱللَّهِ تَطْمَئِنُّ ٱلْقُلُوبُ ﴿28﴾
“Those who have believed and whose hearts are assured by the remembrance of Allah. Unquestionably, by the remembrance of Allah hearts are assured.”
Saheeh International translation
Explanation · Al-Mukhtasar
These people whom Allah guides are those who have faith and whose hearts find comfort in the remembrance of Allah and in His glorification and praise and by reciting and listening to His book. Truly it is only natural that in the remembrance of Allah hearts find comfort.
Reflection
The verse does not say hearts find rest when problems end. It says they find rest in remembrance. Dhikr is available in traffic, at a desk, at 3 am.